Microsoft announced a voluntary replacement program for all Surface Pro AC power cords sold before March 15, 2015, in the U.S. and Canada
and before July 15, 2015, in other markets where Surface is sold. If the cord is wound too tightly, twisted or pinched over an extended period of time there is a potential risk for the AC cordâ€" the cord that connects the power supply unit to the electrical socket â€" to overheat...
To see if you qualify for a free replacement and begin the exchange process, please visit www.surface.com/powercord.
https://blogs.windows.com/devices/2016/01/21/how-to-get-a-replacement-ac-power-cord-for-your-surface-pro/